CZ306697B6 - A method of obtaining concentrates of precious and strategic elements, oxides and minerals by selective magnetic separation - Google Patents

Abstract

The method of obtaining concentrates of precious and strategic elements, oxides and minerals by selective magnetic separation, when, initially, the processed material is subjected to magnetic separation at an induction of 1 to 5 T. Once the magnetic and non-magnetic portion are formed, the magnetic fraction thus obtained is again selectively divided into two portions by the action of a magnetic field weaker than 1 T in the range of 0.1 to 0.35 T, where in the first portion there are more magnetizable substances, these are most often ferro- and ferromagnetic substances often accompanied by precious elements such as lithium Li, rubidium Rb, niobium Nb, etc., and, in the remaining portion, there are worse magnetizable substances, they are usually para- and diamagnetic substances, thereby increasing the concentration of the desired element, oxide or mineral.

Description

Method of obtaining concentrates of rare and strategic elements, oxides and minerals by selective magnetic separation

Field of technology

The subject of the invention is a process for obtaining concentrates of rare and strategic elements, oxides and minerals by selective magnetic separation from the magnetic fraction.

Prior art

Dry and wet magnetic separation in suspension is commonly used to separate magnetizable substances from diamagnetic substances that do not respond to the strength of the magnetic field. For example, kaolins are industrially purified from iron and titanium minerals, various metals are obtained from ballast silicate minerals, etc. Magnetic separation always produces a so-called magnetic fraction, where better or less magnetized substances, elements, oxides or minerals and a non-magnetic fraction are concentrated. which contains non-magnetizable (diamagnetic) elements, oxides or minerals. When it comes to recovering metals and rare elements, oxides or minerals that are well magnetizable in an external magnetic field, then the magnetic fraction is the main component and the ballast, usually silicate or limestone minerals, are contained in the non-magnetic fraction. In the case of cleaning methods using magnetic separation, on the contrary, the magnetic fraction with the accumulation of minerals iron, titanium and other well-magnetized is a by-product or waste (impurity). In these separation processes in a strong magnetic field (magnetic induction 1 to 5 Tesla) the initial distribution of minerals is obtained according to their magnetic susceptibility, but it is not a matter of obtaining concentrates, i.e. increasing the concentration of selected elements, oxides or minerals.

The essence of the invention

The object of the present invention is a process for the treatment of minerals which, by selective magnetic separation, increases the concentration of selected elements, oxides or minerals and separates them from less magnetizable ones. This makes it possible to form concentrates of the desired rare and strategic elements, oxides or minerals, which can be separated from other elements, oxides and minerals.

The subject of the invention is a process for obtaining concentrates of rare and strategic elements, oxides and minerals by selective magnetic separation, in which the material to be treated is first subjected to dry powder magnetic separation or wet magnetic suspension in induction of 1 to 5 T.

The essence of the invention lies in the fact that after the formation of magnetic and non-magnetic part, the obtained magnetic part is again selectively divided by the action of a weaker magnetic field than 1 T in the range of 0.1 to 0.35 T into two parts, where in the first part there are more magnetizable substances. , i.e. ferro and ferromagnetic substances or also mixed substances bound thereto, containing substances selected from the group comprising in particular lithium Li, rubidium Rb, niobium Nb etc. and, in the remainder, generally less magnetizable substances, i.e. steam and diamagnetic substances, thereby increasing the concentration of the desired element, oxide or mineral. In the real implementation of magnetic separation EMS, not only if the natural substances (minerals) can be mixed, both parts can always contain traces of opposite substances, ie in the concentrate of ferro- and ferrimagnetic substances can be part of paramagnetic substances and vice versa . Concentrates of elements, oxides and minerals can thus be formed, which in fact form a mixture of ferro and ferromagnetic substances, through paramagnetic to diamagnetic (for example, the element Bi is entrained in ferromagnetic substances, possibly Li, etc.).

In a preferred embodiment of the invention, after the formation of the magnetic and non-magnetic components, the obtained magnetic component is selectively redistributed by the action of a weak magnetic field with an induction of 0.1 to 0.35 T.

- 1 CZ 306697 B6

The accumulation of selected rare and strategic elements by means of selective magnetic separation in one part and other elements, oxides and minerals in the other part leads to a more efficient use of often unbalanced and as yet unused raw materials.

Increasing the concentration by selective magnetic separation is performed for elements, oxides or minerals including substances selected from the group containing most often iron Fe, manganese Mn, lithium Li, rubidium Rb, cesium Cs, niobium Nb, cobalt Co, nickel Ni, bismuth Bi, thallium TI , Ta tantalum, Sn tin, Ti titanium, Tungsten W etc.

The principle is the selective magnetic separation of selected elements, oxides or minerals in the magnetic fraction obtained, for example, dry in powder or wet in suspension with increased induction of the magnetic field, for example in the range of 1 to 5 Tesla. According to magnetic susceptibility (it is a physical quantity that describes the behavior of the material in an external magnetic field), substances are divided into diamagnetic (they have low and negative values of magnetic susceptibility, this group includes, for example, limestone, dolomite, quartz, graphite, galena, gypsum, diamond , halite, kaolin, feldspar, etc.), which are not magnetizable, paramagnetic (they have small and positive magnetic susceptibility values and this group includes, for example, minerals such as chlorite, pyrite, amphibole, pyroxene, olivine, biotite, etc.) and ferromagnetic , which are the most easily magnetizable in the magnetic field (the best known substances that exhibit ferromagnetism at room temperature are, for example, the elements iron, cobalt, nickel, gadolinium, as well as a large number of alloys and non - metallic compounds). Ferromagnetic substances also include ferromagnetic minerals that are strongly magnetic, exhibit magnetic hysteresis, and retain remanent magnetization even when removed from the magnetic field. Such magnets include, for example, magnetite, titanomagnetite, maghemite, pyrrhotite, goethite, hematite, etc. However, the practical distribution of natural minerals and substances in an external magnetic field need not be unambiguously determined by the influence of mixed minerals.

If we insert the obtained magnetic fraction into a weaker magnetic field with a magnetic induction of 0.1 to 1 Tesla, eg 0.65 Tesla, 0.5 T; 0.35 T, etc. The elements, oxides or minerals contained in it are divided into two parts. On the one hand, ferromagnetic to paramagnetic elements, oxides or minerals are concentrated in the so-called "magnetic fraction" of the obtained magnetic fraction and on the other hand, paramagnetic to diamagnetic elements, oxides or minerals are concentrated in the so-called "non-magnetic fraction". The lower the external magnetic field (magnetic induction), the more concentrates of ferromagnetic substances are obtained in the so-called magnetic fraction after selective magnetic separation. It is thus possible to obtain concentrates of rare or strategic elements such as lithium Li, rubidium Rb, cesium Cs, but also niobium Nb, tantalum Ta or also cobalt Co, nickel Ni, iron Fe, manganese Mn, etc. By sorting (separation) easily magnetizable from weakly magnetizable substances in a weak magnetic field, their concentrates can thus be obtained. Substances less magnetizable are separated from the better magnetized as if in a "non-magnetic fraction". In this way, it is possible to increase the concentrations of the required rare and strategic elements, oxides or minerals. Weak magnetic field with, for example, induction of 0.1 to 0.35 Tesla allows selective magnetic separation to obtain increased concentrations of mica minerals such as cinvaldite, lepidolite, muscovite, biotite, phlogopite, etc. often containing rare lithium, rubidium, cesium, niobium, but also iron, cobalt, nickel, manganese, tantalum, etc., as well as lanthanides (rare earth elements), such as monasites, which contain, for example, rare elements such as cerium Ce, lanthanum La, Th, Nd, Y, etc., or to process and treat ores rich in the mentioned minerals, elements or oxides or granites (granites), pegmatites and other feldspar raw materials, silicate and non-silicate raw materials, dumps, dumps, sludge ponds after ore and non-ore mining, dust, fumes, tablecloths, etc., both in the dry state and in suspensions.

-2EN 306697 B6

Examples of embodiments of the invention

Example 1

Increasing the concentration of rare elements such as lithium Li, rubidium Rb and niobium Nb during the treatment of Krušné hory granite at the Čapí hnízdo O 73-405 deposit by magnetic selective separation. After treating the granite to a fraction of 0.25 to 1 mm, a magnetic fraction containing 0.302 wt.% Was obtained by dry magnetic separation at a magnetic field strength (mag. Induction 1 Tesla). % Li, 0.336 wt. % Rb, 0.151 wt. % Mn, 0.025 wt. % Zn, 0.15 wt. % Bi, 0.010 wt. % Nb, 0.006 wt. % Ta etc.

After a gradual, selective magnetic separation of the magnetic fraction at a weaker magnetic field (successively at 0.65 Tesla, 0.50 Tesla and 0.35 Tesla), the table shows a gradual increase in the concentration of lithium Li and rubidium Rb, including an increase in the rare element niobium Nb.

Field strength / Tesla / Li% Rb% Nb% By% Mn% Zn% Bi% Cr% What% Ta% 1 Tesla 0.302 0.336 0.006 0.151 0.025 0.010 0.006 0.65 0.376 0.418 0.016 0.010 0.185 0.037 0.024 0.007 0.015 0.010 0.50 0.487 0.541 0.019 0.009 0.218 0.061 0.027 0.017 0.010 0.35 0.585 0.022 0.010 0.251 0.072 0.024 0.008 0.029 0.014

Selective magnetic separation increased the lithium Li content from 0.302 wt. % to 0.526 wt. %, increasing the concentration of rubidium Rb from 0.336 wt. % in magnetic fraction to 0.585 wt. % and a concentrate with a niobium content of Nb of 0.022 wt. %.

Example 2

By treating the manganese waste sludge Chvaletice, a magnetic fraction was obtained containing, for example, 10.51 wt. % manganese Mn, 8.10 wt. % iron Fe, 0.003 wt. % vanadium V, 0.007 wt. % chromium Cr, 0.013 wt. % yttrium Y and 0.31 wt. % baria Ba. After gradual selective magnetic separation at lower levels of the magnetic field, manganese concentrate Mn was obtained (increase in concentration from 10.51 wt.% To 13.98 wt.%, Ie an increase of about 3.5 wt.%) / See table / and at the same time rare vanadium, chromium and yttrium were concentrated. It can be seen from the table that the content of barium Ba decreases.

Field strength / Tesla / Mn% Fe% IN % Cr% % Ba% 1 Tesla 10.51 8.10 0.003 0.007 0.013 . 0.31 0.65 11.65 7.90 0.005 0.008 0.016 0.31 0.50 12.45 8.45 0.008 0.009 0.014 0.25 0.35 9.16 0.015 0.018 0.017 0.21

Example 3

Selective magnetic separation has also proved successful in the cleaning of stucco sand (drop from hydrocyclone HC 350 mm) formed during the treatment of kaolin by flotation. The fraction of sand of about 0.063 to 0.50 mm contains as impurities a number of interesting mica minerals, often containing very

-3GB 306697 B6 required rare and strategic elements. These elements, oxides or minerals are separated from the non-magnetic quartz sand by magnetic separation and concentrated in a magnetic fraction which is subjected to selective magnetic separation. For example, stucco sand from the Kaolin mining site Mírová "bílá" contains increased concentrations of Mn, Nb, Co, Ni, Pb, etc. in the magnetic fraction, while the magnetic fraction of stucco sand from the Podlesí II kaolin deposit has increased concentrations of rubidium, lithium, manganese, tin, cobalt, niobium, etc. Magnetic separation of stucco sand provides better quality sand for stucco plaster and at the same time the magnetic fraction is a welcome source of rare and strategic elements. The results of repeated selective magnetic separation at lower levels of the magnetic field strength of the magnetic fraction from the Mírová and Podlesí II stucco sands are given in the table.

Magnetic fraction Peaceful white

Field strength / Tesla / Rb% Mn% Nb% By% What% Pb% Bi% Sn% 1 Tesla 0.093 0.131 0.010 0.005 0.008 0.025 0.65 0.090 0.131 0.017 0.007 0.009 0.007 0.013 0.50 0.060 0.438 0.019 0.014 0.044 0.012 0.008 0.35 0.046 0.022 0.013 0.074 0.018 0.017

Magnetic fraction of Podlesí II

Field strength / Tesla / Rb % Mn% Nb% By% What% Pb % Bi% Sn% 1 Tesla 0.275 0.216 0.008 0.005 0.018 0.017 0.65 0.282 0.315 0.009 0.006 0.031 0.005 0.017 0.016 0.35 0.430 0.011 0.009 0.039 0.010 0.018

Example 4

By using partially gresenitized granites on the Stork's Nest kaolin deposit (sample no. 8, lumps at the sump, 7 July 2016) it is possible to obtain a concentrate of the rare element niobium Nb at a simultaneously high concentration of lithium mica (indication using rubidium Rb). By treating the kaolin by flotation, a yield of more than 0.25 mm was obtained. The fine sand was further subjected to dry magnetic separation on a CARPCO device to induce a 1 Tesla magnetic field. A magnetic fraction with a high proportion of lithium, muscovite and biotite mica containing 0.458 wt. % rubidium Rb, 0.026 wt. % niobium Nb, 0.038 wt. % tin Sn, 0.023 wt. % cobalt Co, 0.019 wt. % bismuth Bi, 0.037 wt. % zinc Zn, 0.245 wt. % manganese Mn, 0.009 wt. % of tantalum Ta, 0.107 wt. % of sulfur S, etc. After repeated selective magnetic separation at lower levels of magnetic field strength, a concentrate of niobium Nb was obtained, as well as a concentrate of lithium Li and rubidium Rb, tantalum Ta and cobalt Co. The results obtained are shown in the table.

Field strength / Tesla / Nb% Rb % Ta% What% Mn% Zn% Bi% By% Sn% Cr% 1 Tesla 0.026 0.458 0.009 0.023 0.245 0.037 0.019 0.038 0.65 0.030 0.511 0.010 0.036 0.313 0.045 0.022 0.005 0.022 0.35 0.017 0.040 0.366 0.062 0.027 0.006 0.014 0.005

-4GB 306697 B6

Example 5

The kaolinized granite Podlesí II L23-425 has an interesting composition of the magnetic fraction in the 0.25 to 1 mm fraction after the wet treatment. When inducing a magnetic field 1, Tesla contains 0.244 wt. % rubidium Rb, 0.138 wt. % manganese Mn, 0.014 wt. % Bi, 0.006 wt. % niobium Nb, 0.003 wt. % of tantalum Ta etc. After repeated selective magnetic separation of the obtained magnetic fraction at a magnetic field intensity below 1 Tesla (0.65, 0.50, 0.35 T), a rubidium concentrate (0.502 wt.%), resp. and lithium with increased content of niobium Nb and tantalum Ta. The high concentration of rubidium Rb also signals an increased amount of the rare element lithium Li and probably also cesium Cs. The results after the proposed adjustment are given in the table.

Magnetic fraction of Podlesí II

Field strength / Tesla / Rb% Mn% Nb% By% What% Ta% Bi% 1 Tesla 0.244 0.138 0.006 0.003 0.014 0.65 0.356 0.205 0.010 0.014 0.006 0.022 0.50 0.421 0.205 0.015 0.008 0.011 0.010 0.027 0.35 0.236 0.014 0.014 0.022 0.011 0.039

Example 6

By processing waste cinvaldite sludge Cínovec, a concentrate of lithium mica cinvaldite (Zinnwaldite) K (Li, Fe ²⁺ , Al) ₃ (Si ₃ Al) Oio (F, OH) ₂ with a high content of lithium Li, rubidium Rb and other strategic minerals, elements and oxides. The original sludge sample (well VD-3, 12.0 to 15.9 m) contained 0.319 wt. % rubidium Rb. The magnetic fraction was obtained in a fraction of 0.063-0.50 mm at a magnetic field strength of 1.0 Tesla and already contained 0.737 wt. % rubidium Rb, 0.544 wt. % manganese Mn, 0.159 wt. % tin Sn, 0.015 wt. % tungsten W, 0.044 wt. % bismuth Bi etc. / see table /.

Magnetic fraction of cinvaldite sludge Cínovec

Field strength / Tesla / Rb% Mn% Sn% By% What% Cr% Bi% Zn% W% Pb% Original 0.319 0.296 0.127 0.024 0.033 0.011 0.008 1 Tesla 0.737 0.544 0.159 0.004 0.009 0.044 0.075 0.014 0.014 0.65 0.849 0.631 0.135 0.005 0.013 0.053 0.089 0.020 0.012 0.50 0.683 0.042 0.010 0.061 0.153 0.023 0.009 0.35 ^ 064 0.716 0.002 0.009 0.013 0.063 0.116 0.026 0.016

The high content of Rb also signals a high concentration of lithium Li, it was also obtained, with a low induction of the magnetic field of 0.35 T, zinc concentrate Zn, Bi, W, etc. From the macrocomponents there is a significant increase in Fe content (from 2.57 wt.% in the original sample of Cínovec sludge up to 4.64 wt.% at induction of 1 Tesla, 6.03 wt.% at a weak magnetic field strength of 0.35 Tesla).

-5CZ 306697 B6

Example 7

Feldspar kaolin with an increased content of lithium mica cinvaldite was first wet-sorted in grain suspension into grain fractions and these were then magnetically separated by inducing a magnetic field of 1.9 Tesla in the fraction below 0.063 mm wet in suspension and 1.7 Tesla in dry on a separator ERIEZ. The magnetic fraction of the grain size fraction 0.2 to 1.0 mm obtained in the dry state by induction of a magnetic field of 1.7 T was then successively subjected to selective magnetic separation at 1 T, 0.65 T, 0.50 T and 0.35 Tesla. The table shows the concentration of selected elements in selective magnetic separation.

Magnetic content of feldspar kaolin

Field strength / Tesla / Rb% Mn% Nb% Th% What% Ba% Bi% AT % Zn% Sr% J Tesla 0.097 0.323 0.009 0.025 0.012 0.055 0.019 0.013 0.033 0.062 0.65 0.092 0.331 0.009 0.022 0.013 0.069 0.020 0.012 0.032 0.062 0.50 0.094 0.316 0.008 0.020 0.008 0.042 0.017 0.009 0.032 0.065 0.35 0.325 0.009 0.020 0.006 0.045 0.023 0.039 0.060

Example 8

After leaching, Kaolin Ruprechtov is stripped of a grain size fraction of 0.063 to 0.20 mm, which has been subjected to magnetic separation at a magnetic field strength of 1.0 Tesla. The magnetic fraction contains, for example, 0.258 wt. % manganese Mn, 0.123 wt. % Rb and the like and from macrocomponents for example 7.45 wt. % iron Fe. Concentrates of iron Fe, cobalt Co and manganese Mn were obtained by selective magnetic separation with lower magnetic field induction (see table).

Magnetic content of Ruprechtov kaolin

Field strength / Tesla / Fe% Mn% What% By% 1 Tesla 7.45 0.258 0.65 13.61 0.468 0.038 0.50 17.85 0.685 0.061 0.006 0.35 0.935 0.101 0.014

The table shows a huge increase in the iron content with the induction of a magnetic field of 0.35 Tesla (from 7.45 wt.% To 23.75 wt.%, Ie a concentration of Fe by 16.3 wt.%!), Manganese from 0.258 wt. . % to almost 1%, cobalt by 0.063 wt. % apod.

Claims (2)

PATENT CLAIMS A process for obtaining concentrates of rare and strategic elements, oxides and minerals by selective magnetic separation, wherein the material to be treated is first subjected to dry powder or wet magnetic separation in suspension by induction of up to 5T, characterized in that after the formation of magnetic and non-magnetic The magnetic fraction thus obtained is again selectively divided by the action of a weaker magnetic field than 1 T in the range of 0.1 to 0.35 T into two parts, where in the first part there are more magnetizable substances, i.e. ferro and ferromagnetic substances or even mixed substances. bound to them, containing substances selected from the group comprising in particular lithium Li, rubidium Rb and niobium Nb, and in the remainder generally less magnetizable substances, i.e. steam and diamagnetic substances, thus increasing the concentration of the desired element, oxide or mineral. Process according to Claim 1, characterized in that the concentration increase by selective magnetic separation is carried out on elements, oxides or minerals comprising substances selected from the group consisting of, for example, iron Fe, manganese Mn, lithium Li, rubidium Rb, cesium Cs, niobium Nb , cobalt Co, nickel Ni, bismuth Bi, thallium TI, tantalum Ta, tin Sn, titanium Ti and tungsten W, thus creating concentrates of rare and strategic elements, oxides or minerals.